The GSM character set extends the ASCII character set to include characters from many European
languages, for example, characters such as Σ, Ç and Æ. Connection Software fully supports sending
SMS text messages using the GSM character set. When using the GSM character set messages are limited
to 160 characters per SMS. All our APIs support the sending of longer messages, which we send to the
phone as multiple concatenated SMS messages.

The Unicode standard enables you to send SMS text messages using an characters from any written
language. Connection Software fully supports sending SMS text messages using the Unicode character
set, however messages are limited to 70 characters per SMS. All our APIs support the sending of
longer messages, which we send to the phone as multiple concatenated SMS messages.

Some additional characters can be sent using the [Escape] code in the above
table plus an additional character

You want to send ASCII

Send the following

Decimal

Hex

Char

Decimal

Hex

Char

€

27 101

1B 65

[Escape] e

10

0C

[Form feed]

27 10

1B 0A

[Escape] [Line feed]

91

5B

[

27 60

1B 3C

[Escape] <

92

5C

\

27 47

1B 2F

[Escape] /

93

5D

]

27 62

1B 3E

[Escape] >

94

5E

^

27 20

1B 14

[Escape] ^

123

7B

{

27 40

1B 28

[Escape] (

124

7C

|

27 64

1B 40

[Escape] @

125

7D

}

27 41

1B 29

[Escape] )

126

7E

~

27 61

1B 3D

[Escape] =

Unicode Standard

Connection Software fully supports sending SMS text messages using the Unicode character
set (limited to 70 characters per SMS). All our APIs support the sending of longer messages,
which we send to the phone as multiple concatenated SMS messages. Please refer to documentation
from The Unicode Consortium and the
Unicode FAQ for more details about
Unicode. All our APIs support the UTF-8 encoding for Unicode messages, except SMPP which supports
UCS-2 encoding.

Why are Unicode messages limited to 70 characters?

A GSM SMS can contain a message payload of
up to 140 octets (8-bit bytes). The GSM Default Alphabet is a 7-bit alphabet, so it’s possible to
pack up to (140*8)/7 = 160 characters in a single SMS. Unicode messages are encoded using UCS-2
which requires 2 octets per character, so it is only possible to pack up to 140/2 = 70 characters
into a single SMS.

HTTP Encoding

When you submit messages to our servers though our
HTTP to SMS API you must use HTTP encoding for the characters shown in the table below.